LeRouret

Absolutely...the Romain canal tiles are really childs-play..fix first and last row...remaining just placed with no fixation so relaying tiles for 100 m2 is probably half days work... I think 4k is about right for materials for 150 mm...even if I assume 250 day labour per person....two people five days is 2.5k....so I can get to 7k in total but down here the wankers will charge at least double... I am still considering a cold roof for simplicity and as a temporary measure... One thing I have to deal with with the strategy you have described is how to deal with the ridge...I guess I would have to do the other side as well..

@Radian One thing...weight. Considerations ??

@Radian Thanks, very clear, understood. I am going to lift some tiles off and see exactly what is going on. As a matter of curiosity...for the scheme described, 100 m2, how much would you charge ? And how long would it take two people ? Thanks again.

Thanks all for comments....as you all know the roof/insulation is shambolic...this is France. I am very reticent to get a "professional" (or "artisan" as they are called in France) down here to have a look...if you think you have seen cowboys in the UK, think again..having sorted out electrics and plumbing I am not going to let an Artisan anywhere near this house.. I don't even need to ask but I think they will charge about 20k just to strip tiles and put insulation down...and will not be a good job...in other words I want to do it myself. I think I will have to compromise on the amount of insulation but that is OK if I can avoid condensation. @ProDave How much work ? Of course you are right - effectively starting again is the ideal fix - so I want to cost and have some idea of the complexity for two solutions (i) The solution you have proposed and (ii) Cold roof within the limites of not starting over again @Dave Jones Thanks - yes that looks like my "compromise"...looks like I can get Tyvec here as well...I guess I have to glue the PU panels to the plasterboard ceiling, I assume weight is not an issue ? @RadianI am being a bit thick here...are you suggesting I add OSB ? Recall (from piccy below of how roof is constructed) all I have is plasterboard->100 mm space->Triangular battens->Tiles

Hello Mr P and thanks.. I can probably remove a few of the triangular battons and slide the panels under. Not sure how I am going to attach them..I can glue the vapour barrier to the plasterboard and then glue panels to vapour barrier…I just need to stop them moving when it’s windy…does not seem ideal… I can barely lower the ceiling…the lowest point by the big windows only gives me about 30mm before I violate building regs

Hello. We bought a house in France and clearly have condensation problems in the lounge/roof. The lounge is big - 7m X 6m - and has what the Frogs call a "Cathedral Ceiling". There is no "loft" space in the lounge, just plasterboard, minimal insulation in places and then "roman" tiles. Note - the way roofs are done here a somewhat different to the UK - our roman tiles/roof is very typical in the south of France. House built 1970. Attached are various pictures and a graphic of how the tiles are put together on the roof - only the first row and last row of tiles are fixed...the remaining are just placed with no fixation. The slope of the roof is fairly steep...see piccy with Christmas tree :-) You can see the minimal insulation with the inspection camera image - this is by the windows where the condensation is worse - presumably because warm air meeting the cold plasterboard and this is where the minimal/none insulation is. Our heating is reversible air-con so not sure how this helps with lounge humidity and condensation. Some advice on how to remedy this ? I can take all the tiles off for access - as stated, they are not fixed - except first and last row. I want to keep the existing plasterboard. And can't even lower the ceiling for more insulation as it will fail building regs. Between tiles and plasterboard the gap is approx. 10 cm. All I can do, I think, is add a vapour barrier than say 80 cm of insulation....something like this: https://www.castorama.fr/panneau-d-isolation-thermique-polyurethane-2-5-x-1-2-82-mm/5411545052587_CAFR.prd Thanks in advance.